Breaker-point dresser



Oct. 30, 1934. c. .1. STOCKER 15978379 BREAKER POINT DRES SER Filed Feb. 7, 1933 Patented Oct. 30, 1934 1,978,479 BREAKER-POINT nREssER Charles J. Stocker, Salt Lake City, Utah Application February '1, 1933,. :Serial No. 655,604-

6 Claims.

This invention relates to a breaker-point dresser and its principal object is to provide a simple and convenient tool by means of which the breaker-points of electrical devices, such as distributor heads used" in automobiles, may be accurately an'd expeditiously ground or dressed.

Breaker-points are subject to electrical arcing, which results in corrosion and pitting of the contactsurfaces. At the same time, the mountings onwhichthe breaker-points are supported, are liable to be bent or otherwise distorted. All these causes result, inpoor electrical contactsbetween the'surfaces of mating points, which contacts; however) can be perfectly restored, by grinding the faces true and square.

In the present invention, the arms on which the breaker points are carried, are temporarily protection of LettersPatent of thefUnited States isfdesired, are collectively grouped in the claims concluding this specification.

In the drawing,which illustrates one embodiment' of this invention, t

Fig lrepresen'tsa" side elevation, partly in sectionf T an'end elevation partly in section, a

, breaker arm being shown in position ready for grinding? Fig. 3, a side elevation showing the present device with a breaker-point in place on a Whetstone in the grinding position; the location of a users hand being indicated; and

' Fig. 4, a top plan corresponding to Fig. 3, partly in section, taken on line 4-4, in Fig. 1.

Referring to the drawing, the numeral 10 indicates a foundation or datum block, which carries 1a holder block 12 and a guide block 14. The holder block and guide block are preferably movable, relative to each other and to the foundation block, for the purpose of adjustment to the individual requirements of different breaker point m- 'mountings.

The movement of the holder block may be angular about a hinge pivot 15, while the movement of the guide block may also be angular, but

about another hinge pivot 16. The movements of the two hinged blocks are limited, and are preferably in planes substantially at right anglesto each other. I

. Pivot 15 may be disposed in lugs 1'7 and'18 projecting respectively from the holder block and foundation block; and similarly, pivot 16 may be disposed in lugs 19 and 20.

As'shown in the present drawing, both'hinged blocks may be spaced apart from the foundation block what may be called the normal positions where the upper faces of the hinged blocks are substantially parallel to the lower face of the foundation block, so that if it shouldbecome desirable at any time, an angular adjustment towards the foundation block may be effected.

In order to hold thenorrnal positions of the hinged-blocks 12 and 14,:stops in the form of screws 21 and 24, respectively, may be threaded in the foundation block, these screws being suitably retracted when other adjustments within their adjusting limits are desired.--

Thehingedblocks arepreferably held yieldingly in contact with the respective stops 21 and 24, by means of the respective tension springs 25 and 26. Spring 25 may have one end thereof pinned at 27in the foundation block, andth'e other endat 28 in the holder block, while spring- 26 may have one end thereof pinned'at 29 in the foundation block and" the other end at 30 in the guide block.

For the purpose of effecting temporary adjustments of "the hinged blocks angularly away from the positionsshown inthe drawing, towardsone side or th'e'other to suit the particular requirements of individual breaker-points, screws 3land 32? are pr'ovi'dedr Thesescrewsmay have knurled heads for manipi-ilation with thumb and fingers.

As a matter of convenience, the holder block may be bifurcated so as to provide two legs 34 and 35, and the guide block may be similarly bifurcated to provide two legs 36 and 37. These latter have their lower surfaces 38 and 39, respectively, smoothed off true and exact, and are preferably hardened for the purpose of riding on a grinding face of a Whetstone 40.

It is to be noted that breaker-point mountings are of many different kinds, so that in a tool for general use, provision should be made for accommodating mountings of a variety of designs and dimensions. This is accomplished in the present invention, by making the holder block quite extensive both below and above the grinding plane 41.

At 42 is an example of a breaker-point arm pivoted on a pin 44, which latter may be removably disposed in a hole 45, the breaker point being located at 43. Another example is indicated in dotted lines at 52, the arm being pivoted on a removable pin 54 disposed in a hole 55, the breaker point in this instance being located at 53.

In using this tool, the breaker arm, for instance 42, supported on pin 44, has the exact position, respecting grinding plane 41, that it would occupy in a distributor (not shown) relative to the contacting face of the mating point (not shown).

The user grasps the tool with its temporarily mounted breaker arm, between the thumb and fingers of one hand, somewhat as indicated in Fig. 3, and draws the tool lightly back and forth, substantially as indicated by the double-pointed arrow in Fig. 4, along the grinding plane 41, meanwhile using the finger to exert the proper pressure upon the breaker arm so as to bring about the proper grinding of the facial surface of point 43.

The axes of the breaker-arm pivots may lie above or below the grinding plane, and too, the radial distance from the pivot to the breakerpoint stub may vary considerably. Therefore, the area of holder block 12 is made sufiiciently large, as indicated in Figs. 1 and 3, to contain any desired number of holes, for example, 47 to 49, in addition to the ones at and 55. This brings the depending portion of the holder block below the grinding face 41 and at the same time provides a guide along the side face of the whetstone. The diameters of holes 45 to 49 are, of course, made to accommodate pins (only 44 and indicated) of various diameters corresponding to the pivots of the different breaker arms.

While a specific embodiment of this invention is herein shown and described, it should be clearly understood that various changes in the details thereof, can easily be made without departing from the spirit and scope of the following claims.

Having fully described my invention, what I claim is:

1. A breaker-point dresser, including in combination, a foundation block, a holder movably mounted thereon, a guide member movably mounted on the foundation block and in operative proximity to the holder, said guide member having a grinding guide face, means for mounting a breaker-point arm on said holder, said breakerpoint arm carrying a breaker-point, and. means whereby the position of the grinding guide may be adjusted to bring the guide face thereof into the required face plane of the breaker-point.

2. A breaker-point dresser, including in combination, a foundation block, a holder movably mounted thereon, a pivot whereby a breaker-point arm may be mounted on said holder, means whereby the holder may be adjusted to vary the distance from the axis of said pivot to said foundation block as well as the angular relation between them, and guiding means movably disposed relative to the foundation block for the purpose of adjustment.

3. A breaker-point dresser, including in combination, a foundation block, a holder block hinged thereon, a guide block hinged on the foundation block in proximity to the holder block, the holder block and guide block being disposed to swing in planes substantially at right angles to each other, a pivot pin disposed in the said holder block with its axis substantially parallel to the axis of the holder block hinge, and means whereby said holder block and said guide block may be angularly adjusted relative to said foundation block.

4. A breaker-point dresser, including in combination, a foundation block, a holder hinged thereon, a guide block hinged on the foundation block in proximity to the holder and disposed to have angular motion in a plane at substantially right angles to a plane in which the holder has angular motion, tension springs disposed to draw the free ends of the holder and the guide block towards the foundation block, and adjusting screws threaded in the foundation block, said screws bearing respectively against the holder and against the guide block and being opposed to the tension of said springs.

5. A breaker-point dresser, including in combination, a foundation block, a holder adjustably mounted thereon, means for pivotally carrying a breaker-point arm on said holder, a guide block hinged on the foundation block and having motion in a plane substantially at right angles to the plane of motion of the breaker-point arm around its pivot, and means for adjustably fastening the free end of said guide block to the foundation block.

6. A breaker-point dresser, including in combination, a holder, means whereby a breaker-point arm may be pivotally mounted on the holder, a guide block having a guide face in proximity to said holder, and supporting means in common for the holder and the guide block, the holder and guide block being adjustable relative to the supporting means independent of each other, to the end that said guide face is adapted to ride on a grinding surface and said breaker-point arm is disposed to cause the face of its breaker-point to contact the said grinding-surface in any required plane.

CHARLES J. STOCKER. 

